1. Field of the Invention
The present invention pertains generally to the field of emergency warning and alarm systems and is more particularly directed to an indicator system suitable for domestic use which is actuated upon dialing of a telephone number sequence associated with an emergency assistance service and when actuated activates a strobe or other indicator exterior to the premises for attracting and guiding personnel responding to the call.
2. State of the Prior Art
Emergency assistance services in urban areas are called upon in emergency situations where very short time spans can make the difference between success and failure in saving a life. Paramedic teams increasingly possess the capability of rescuing victims of accident or illness who may have undergone cardiac arrest, massive blood loss or otherwise be in a condition where life expectancy may be measured in seconds. If average response times in such situations can be reduced by as little as a few seconds an improvement in the rescue success rate is certain to result. Similar operating parameters exist for fire fighting teams or police personnel. Widely available smoke detecting equipment is capable of sensing a fire at its earliest stages when it can be easily extinguished. However, a very small fire can quickly spread into a major conflagration and again response time is critical. Likewise, even a few seconds gained in reaching the scene may avoid serious injury when police responds to a call for assistance.
In recognition of the need for ever increasing speed, centralized emergency telephone services have been implemented in many metropolitan areas, such as the well known 911 emergency assistance service. These services are supported by the local telephone companies so that dispatch personnel receiving a call at the 9-1 number is immediately provided with the street address at which the telephone call originates. The 911 dispatch center therefore only requires a general indication of the nature of the emergency from the caller in order to dispatch the proper type of help, without having to obtain accurate directions from an individual who may be unable to provide them.
Once the response team, whether an ambulance, fire engine or police vehicle, nears the address at which the request for assistance originated, the responding personnel is usually forced to proceed at a very deliberate pace in order to locate the exact street address. Particularly at night, the task of finding a particular house along a dark street is often inordinately difficult. In many areas, it is up to the homeowner to place address numerals on the residence. This is often done in a haphazard manner with numerals of all sizes, styles and colors mounted in unpredictable locations which may be poorly lit or obsured by garden vegetation etc. Emergency personnel responding to a call are thus often forced to proceed at a crawl along the street searching for a particular number, with the aid of a searchlight when at night. It is awkward for emergency vehicles such as ambulances or fire engines to back-up and therefore, rather than risk passing by the desired house number, the drivers proceed with excessive caution while attempting to locate the desired address.
What is therefore needed is a system capable of activating a readily visible indicator, preferably a visual indicator such as a strobe light, mounted exteriorly to the housing or other premises and which is activated upon making a telephone request for emergency assistance. Furthermore, it is desirable that such a system operate automatically without the deliberate intervention of any persons at the emergency site so as to insure its actuation merely upon the dialing of a telephone number sequence associated with an emergency assistance service.
Some existing alarm systems do feature a combination of automatic telephone dialing and activation of an exteriorly perceptible indicator, such as either a horn alarm or a flashing light or both, upon triggering of the alarm system. In such arrangements, the exterior lamp or horn does operate to attract attention to the affected premises, but only in response to actuation of the alarm system and independently of the automatic telephone dialing which places the call for assistance. Such existing arrangements are inadequate for the purposes described above.